A new moment-resisting precast concrete beam and column joint system using untensioned wire strands was developed in the study, mainly for the use in underground parking lot in which the influences of the seismic load may be neglected. For the evaluation of the performance of this new joint system, the behaviors of the beams, reinforced by the deformed bars and the untensioned strands in combination were experimentally investigated. The reinforcement ratio of the wire strand to the deformed bar was selected as the test parameter. The test results showed that the flexural capacities of all five specimens were sufficient. However, the wire strand ratio has to be used limitedly in the aspect of the serviceability due to the large deflection.